Abrasive throwing wheel distribution system

ABSTRACT

An abrasive throwing wheel distribution system operates without the use of a conventional distribution screw by including a plurality of separating units symmetrically arranged for receiving an abrasive particles containing mixture. The abrasive particles are removed from the mixture and fed to abrasive throwing wheels.

United States Patent 119i Rowe July 3, 1973 [54] ABRASIVE THROWING WHEEL2,131,769 10/1938 Tumbull 51/9 DISTRIBUTION SYSTEM 2,231,951 2/1941Rosenberger. 51/9 I 2,239,714 4/1941 Hammell 51/9 [75] inventor: RussellL. Rowe, Hagerstown, Md. 2,276,345 3 1942 Rosenberger, 51/9 [73]Assisnee: I Thercarborundum p y 3,161,991 12/1964 Powell et al. 51/9Niagara Falls, N.Y.' FOREIGN PATENTS OR APPLICATIONS 22 Filed; 13, 1970937,628 9/1963 Great Britain 51/8 [21] Appl' 63452 PrimaryExaminer-Harold D. Whitehead Attorney-David E. Dougherty'and Robert E.Walter [52] US. Cl. 51/9, 209/134 [51] Int. Cl. B242 7/00, 1307b 4/02 57ABSTRACT [58} Field of Search 51/9, 8, l2;

209M154, 135, 136, 137 254; 241/135 An abrasive throwing wheeldistribution system operates without the use of a conventionaldistribution [56] References Cited screw by including a plurality ofseparating units symmetrically arranged for receiving an abrasiveparticles UNITED STATES PATENTS containing mixture. The abrasiveparticles are removed 321,030 6/1885 Hutchison 241/135 f the mixture andf d to abrasive throwing wheels, 2,866,547 12/1958 Gladfelter et al.....209/135 X 3,368,677 2/1968 Bradley,Jr .1 ..209/135 10 Claims, 4 DrawingFigures PATENIEuJum 1915 3.742 651 ml 2 or 2 ABRASIVE THROWING WHEELDISTRIBUTION SYSTEM BACKGROUND OF INVENTION This invention relates to anabrasive throwing wheel 7 distribution system which omits theconventional distribution screw. With the conventional arrangements anelevator delivers the mixture to a distribution screw which distributesthe mixture over an elongated area along the length of the screw toseparating means disposed beneath the screw. A disadvantage with such anarrangement, however, is that the separators at the furthest distancefrom the elevator do not receive enough abrasive which results instarving some of the abrasive throwing wheels. A further seriousdisadvantage with these conventional arrangements is that in largeinstallations the screw is quite large and since it is a rotating memberit presents serious maintenance problems.

SUMMARY OF INVENTION An object of this invention is to provide anabrasive throwing wheel distribution system which omits the conventionaldistribution screw.

A further object of this invention is to provide such a system whichavoids the starving of abrasive to the throwing wheels.

A still further object of this invention is to provide such a systemwhich has minimal maintenance problems.

In accordance with this invention an abrasive throwing wheel systemoperates without the use of a conventional distribution screw byincluding a plurality of separating units symmetrically arranged forreceiving an abrasive particles containing mixture. The abrasiveparticles are removed from the mixture and fed to abrasive throwingwheels.

The separating units may comprise four individual units of the air-washtype arranged in a cluster in a boxlike manner. Additionally, a singlefeed hopper may be used for receiving the abrasive particles removedfrom the mixture by the separating units, with the hopper thereafterfeeding the particles to the throwing wheels. Advantageously levelindicating means may be provided in the feed hopper to preventoverfllling, and additional level indicating means may be provided inthe receiving bin which supplies the mixture to the separating units tomaintain flow of the mixture to the unit.

THE DRAWINGS FIG. 1 is a schematic showing of a prior art arrangementincorporating a conventional distribution screw;

FIG. 2 is a schematic showing partly in section of an abrasive throwingwheel distribution system in accordance with this invention;

FIG. 3 is a cross-sectional view taken through FIG. 2 along the line3-3; and FIG. 4 is a side elevation view of a portion of the systemshown in FIG. 2.

DETAILED DESCRIPTION FIG. 1 shows a prior art arrangement which includesan elevator 12 for receiving and delivering a mixture of spent abrasive,fines, etc., from the throwing wheels and from the work pieces beingtreated, to a feed screw and scalping drum 14. The mixture is thendelivered to a distribution screw 16 which deposits the mixture intoindividual separating units 18. In these separating units the abrasiveparticles 20 are removed from the mixture and supplied to feed hopper22. At times the bed of abrasive particles 20 assumes an angle of reposesimilar to that shown in FIG. 1. This angle of repose results from theseparator 18 located the furthest distance from elevator 12 not beingsupplied sufficient mixture by the distribution screw 16. As a result ofthis the corresponding blast wheel would be starved since insufficientabrasive particles would be fed to it. A number of disadvantages arereadily apparent from such a system including the insufficient treatingof the work piece. Moreover because distribution screw 16 is a rotatingmember and thus, for example, must include bearings 24 maintenanceproblems are created by this arrangement.

FIGS. 2-4 show an abrasive throwing wheel distribution system 30 inaccordance with this invention. In general the system 30 also includesan elevator 32 which recirculates or supplies an abrasive particlescontaining mixture 34 to a cluster of individual separating units 36 bymeans of feed screw and scalping drum 38 communicating with receivingbin 40. An overflow conduit 42 is provided for feed screw and scalpingdrum 38 should an excessive amount of mixture be supplied thereto.

The bin 40 has side walls 80, end walls 82 and bottom 83. The bottom 83slopes downwardly from a raised portion to lower portions 87 which areadjacent side walls 80. As illustrated in the drawings, the bottom 83has an inverted V-shape with the raised portion 85 at the top of theinverted V and the lower portions 87 at the bottom of the inverted Vadjacent the side walls 80. A plurality of openings 62 are located ineach of the lower portions 87 of the bottom 83. The openings 62 are ofsubstantially equal size and are symmetrically arranged. Theconfiguration of the openings 62 and bottom 83 results in an excessmixture within the bin 40 being evenly distributed over the openings 62to form a bed 34 covering the openings 62.

As shown in FIG. 4, the separating units 36 are arranged under bin 40 ina cluster in a box-like manner whereby each unit is disposed at thecorner of a box. By this arrangement, there is equal distribution of themixture through openings 62 into each of the separating units.Accordingly, by this arrangement none of the separating units wouldreceive an insufficient supply of mixture which in turn would have ledto the starving of certain blast wheels.

Separating units 36 may take any suitable form such as being of theair-wash type as disclosed in U. S. Pat. No. 3,368,677 the details ofwhich are incorporated herein by reference thereto. Essentially, eachseparating unit includes suction means 44 for drawing an air curtain orstream through inlet 46. The falling mixture passes over metering gate48 and is exposed to the air stream whereby in conjunction with anysuitable number of skimmer plates 50 the mixture is subdivided in anydesired manner or number of sub-streams and includes for example pureabrasive particles 52 aswell as any suitable number of correspondinglylighter submixtures. The abrasive particles from all separating unitsare collected in a single hopper 54. Hopper 54 includes a plurality ofopenings 89 with each opening being disposed under a respectiveseparating unit 36 so as to receive abrasive particles therefrom.Separating units 36 also include overflow means 56 for excessive pureabrasive particles or for a mixture of pure abrasive particles andheavier contaminants. Additionally,

means 58 are provided to receive the lines or other light weightcontaminants. From the feed hopper 54 the abrasive particles are fedthrough supply tubes 60 to the individual blast wheels (not shown) ofthe conventional centrifugal throwing wheel type.

As shown in FIGS. 2 and 4 the feed hopper 54 receives 'pure abrasiveparticles 52 from the individual separators 36 in such a manner thatthere are actually four angles of repose or beds in contrast to thesingle angle of repose resulting with prior art arrangements. Moreoverthe deepest portion of each bed of abrasive particles is disposeddirectly over the feed conduit 60. This also assists in preventing thestarving of blast wheels.

The central portion of feed hopper 54 also includes an inverted conicaltype chamber 64 which comprises part of the overflow means 56 andcommunicates with overflow conduit 66. Similarly, within the chamber 64is arranged a further Y-shaped chamber 68 for receiving the fines fromthe individual separators 36 and discharging them through spouts 70. Thechamber 68 and spout 70 thus comprise the main elements of means 58. Asis apparent from the drawings the single chamber 64 and the singlechamber 68 each communicate with all of the separators 36.

As also shown in FIG. 2 a suitable level indicating means 72 is providedin feed hopper 54 to prevent over filling of this feed hopper.Similarly, level indicating means 74 is provided in bin 40 for use as ar'eplenisher to assure the maintenance of flow of the mixture 34 to theindividual separating units 36.

What is claimed is: I

1. An abrasive throwing wheel apparatus comprising a receiving binhaving side walls and a bottom, said bottom sloping downwardly from araised portion to lower portions, each lower portion being adjacent aside wall, means for feeding an abrasive particle containing mixture tosaid receiving bin, each lower portion having a plurality of openingstherein, said openings permitting the mixture received in said bin to bedistributed through the openings in substantially equal portions, aplurality of separating units symmetrically arranged under saidreceiving bin, each of said separating units communicating with one ofthe openings to permit the mixture to flow into said separating units,separating means in each of said separating units for removing abrasiveparticles from the remainder of the mixture, collecting means connectedto each of said separating units for collecting the remainder of themixture, feed hopper means communicating with each of said separatingunits for receiving the abrasive particles removed from the mixture, aplurality of abrasive throwing wheels, and feed means connected to saidfeed hopper means and said abrasive throwing wheels for feeding abrasiveparticles to said throwing wheels.

2. An apparatus as set forth in claim 1 wherein feed hopper means is asingle feed hopper.

3. An apparatus as set forth in claim 2 wherein said separating unitscomprise four separator units clustered together in a box-like mannerwhereby each of the units are disposed at the corners of a box.

4. An apparatus as set forth in claim 3 wherein each unit is of theair-wash type.

5. An apparatus as set forth in claim 4 wherein level indicating meansare in said feed hopper to prevent over filling of said feed hopper.

6. An apparatus as set forth in claim 5 wherein level indicating meansare in said receiving bin to maintain flow of the mixture to said units.

7. An apparatus as set forth in claim 6 wherein said means for feedingan abrasive particle mixture includes an elevator and a scalping drum.

8. An apparatus as set forth in claim 7 wherein said collecting meansincludes an inverted conical abrasive particles overflow chamber withinsaid feed hopper and a Y-shaped fines chamber.

9(An apparatus as set forth in claim 2 wherein each separating unit hasan abrasive particles outlet communicating with said hopper, and saidfeed means for each of said throwing wheels being directly under arespective outlet.

10. An apparatus as set forth in claim 3 wherein said feed hopperincludes a plurality of openings therein, each opening being disposedfor receiving abrasive particles from a respective separating unit.

It a =c=

1. An abrasive throwing wheel apparatus comprising a receiving binhaving side walls and a bottom, said bottom sloping downwardly from araised portion to lower portions, each lower portion being adjacent aside wall, means for feeding an abrasive particle containing mixture tosaid receiving bin, each lower portion having a plurality of openingstherein, said openings permitting the mixture received in said bin to bedistributed through the openings in substantially equal portions, aplurality of separating units symmetrically arranged under saidreceiving bin, each of said separating units communicating with one ofthe openings to permit the mixture to flow into said separating units,separating means in each of said separating units for removing abrasiveparticles from the remainder of the mixture, collecting means connectedto each of said separating units for collecting the remainder of themixture, feed hopper means communicating with each of said separatingunits for receiving the abrasive particles removed from the mixture, aplurality of abrasive throwing wheels, and feed means connected to saidfeed hopper means and said abrasive throwing wheels for feeding abrasiveparticles to said throwing wheels.
 2. An apparatus as set forth in claim1 wherein feed hopper means is a single feed hopper.
 3. An apparatus asset forth in claim 2 wherein said separating units comprise fourseparator units clustered together in a box-like manner whereby each ofthe units are disposed at the corners of a box.
 4. An apparatus as setforth in claim 3 wherein each unit is of the air-wash type.
 5. Anapparatus as set forth in claim 4 wherein level indicating means are insaid feed hopper to prevent over filling of said feed hopper.
 6. Anapparatus as set forth in claim 5 wherein level indicating means are insaid receiving bin to maintain flow of the mixture to said units.
 7. Anapparatus as set forth in claim 6 wherein said means for feeding anabrasive particle mixture includes an elevator and a scalping drum. 8.An apparatus as set forth in claim 7 wherein said collecting meansincludes an inverted conical abrasive particles overflow chamber withinsaid feed hopper and a Y-shaped fines chamber.
 9. An apparatus as setforth in claim 2 wherein each separating unit has an abrasive particlesoutlet communicating with said hopper, and said feed means for each ofsaid throwing wheels being directly under a respective outlet.
 10. Anapparatus as set forth in claim 3 wherein said feed hopper includes aplurality of openings therein, each opening being disposed for receivingabrasive particles from a respective separating unit.